There a misconception about D series blades cutting for 6 months no matter how you take care of them...WRONG! The D series blades are no different than your regular A series blades that fit your regular clipper, if you don’t clean and oil them properly they will dull prematurely.
The biggest problem with D series blades not cutting is the clipper themselves and you don’t even realize it. There are D series cordless clippers on the market that use NiCAD/NiMH batteries as a power source. These batteries could be questionable batteries to use in a cordless clipper for several reasons.
1. These batteries could get a power memory very easy. Once this memory is reached, the power starts to go down in the battery quickly. The torque could go down as well, torque is what holds speed up.
2. Keeping the clipper with these batteries in the charger when not in use could damage the cells of the battery. Its best to use the clipper until the battery depletes all the power, then put it in the charger, and take it out when fully charged. WHY? Because some can’t take continuous charging, it can melt the cell membranes and lower the life of the battery. This is how the memory is put in these types of batteries.
The best rule of thumb is, no matter what your manual says, if its a NiCAD or NiMH battery don’t leave it cooking in the charger all the time when your not using it. Don’t use it for a short time and put it back in the charger, charge it only when its goes dead and don’t overcharge. Some chargers for these batteries are very cheap and most only have a red and green light on them. When the green light comes on it may not shut the charging completely off, current can still trickle into the battery causing cell wall damage.
When the power in the battery starts to go down, the speed of some clippers goes down. This can cause problems with the blades cutting. They can go through coat fine for a short time and then start to drag or snag. With cordless clippers using NiCad/NiMH batteries, the speed and torque of the clipper could slow down ever so slowly that you may never notice it until blades start having issues. You may have sent blades off for sharpening because you thought they were dull or dulling, but it could have been the clipper.
How do we fix this problem?
Most problems with batteries are caused by the customer overcharging them. They can last years if charged properly, but most manuals do not cover good charging practices. In my opinion, Lithium batteries should follow good charging practices also.
You can also buy a corded D series clipper. Northern Tails sells a corded D series clipper. www.ntforsale.com
If your set on a cordless D series clipper, our advice is to wait until a Lithium based unit is available. Lithium batteries are more forgiving and usually can power the cordless clipper longer before recharging is needed.
Here at Northern Tails Sharpening, we have been resharpening D series blades since the late 90’s when they were first introduced. We test each blade on actual fur to make sure it cuts, and we use a CORDED D series clipper. WHY? Because the speed is steady and doesn’t fluctuate like it does on some cordless models.
So, if you just got D series blades back from us and they drag or snag, the problem most likely is on your end because they cut on our corded clipper through fur. They may keep having issues until you get new batteries or a new charger for them. Remember there are corded models that run so much better.
This is just our opinion from years of dealing with D series equipment.
We also have a YouTube page with video's on how to take care of your D series equipment and many other video's on equipment care. Click on or copy/paste this link:
Have a great day grooming and stay healthy